All your intellectual understanding of spirituality is just knowledge that belongs to others, your parents, teachers, saints, scriptures, gathered and stored as data in your brain bank.
You can convince others and your ignorant mind that you know. Until you find yourself in the situation where your intellect fails and your deepest core cries for help from God, and you feel it deeply, only then it is yours. Borrowed knowledge is good for the world. Direct knowledge makes you wise. It comes out of practice, practice, practice of what you know. Don’t stop till you have found that One reality behind all temporary fleeting appearances.